1. Field Of The Invention
The present invention relates to a method for cleaning the interior surfaces of a water-containing vessel, and more particularly to a method for removing stains, scale, calcium deposits and the like from the walls and bottom of a swimming pool or the like, in-situ, and without the need for draining the water from the pool.
2. Brief Description Of The Prior Art
There are no known prior art patents even remotely related to the method of the present invention. However, the closest known patent in U.S. Pat. No. 4,906,384, which issused on Mar. 20, 1989 to Jock Hamilton for a NO DRAIN ACID TREATMENT OF POOLS. This patent teaches a method for treating the water within a swimming pool for removing scale deposits from the interior surfaces of the pool containing the water. The patent specifically teaches acidifying the pool water a mixture of hydrochloric acid, sulfamic acid, and sodium bisulfate to eliminate its total alkalinity. The water must be continually monitored throughout the entire process for total alkalinity. After the acid treatment, all excess treatment acid is neutralized by magnesium oxide or magnesium hydroxide as the normal alkalinity of the pool is restored.
This method requires a large quantity of chemicals since all of the water in the pool is treated simultaneously. The need for continual monitoring or testing is very time consuming and critical to the process. Thus, it may prove quite difficult when the process is to be used by ordinary pool owners.
Furthermore, since the stain and scale-causing chemicals remain in solution in the swimming pool, and in spite of the inventor's allegation that scales will not reform immediately thereafter, they will reform rather quickly over a short period of time. Still further, since all of the pool water is treated, the treatment process takes a relatively long time to complete.
Since the acid solution is added to the pool water in general, it is relatively dilute, thus taking a long time to work. Also, the chemicals used will cause real damage to the pool circulation system since the inventor does not disable the system during the treatment process. Since he does not adjust the chlorine level initially, excessive algae growth will present another very real problem. Further yet, the by-products of his chemicals are very, very difficult to remove from the system when they are left in the pool since they quickly combine with clay particles, silica, and the like to form scale deposits on the interior pool surfaces which are even more difficult to remove than the original calcium deposits.
These and other problems of this prior art method and others of the prior art are solved without producing any new problems, by the method of the present invention as hereinafter described.